Improvement in devices for refitting valve-seats



V c. r. HALL. DEVICE FOR mmmme VALVE-SEATS. N.17o,3e3, Patented Nov.23,1875.

" ajignl.

Wimwm: um 01," W-

' gttumegfi.

N. PETERS. Pfi0TOLITNOGRAPNER, WASHINGTON. D. C.

UNITED STATES PATEN QFFIGE.

CHARLES F. HALL, OF SKANEATELES, NEW YORK.

IMPROVEMENT IN DEVICES FOR REFITTING VALVE'SEATS.

Specification forming part of Letters Patent No. 170,363, dated November23, 1875; application filed February 16, 1875.

CAsE A.

To all whom it may concern:

Be it known that I, CHARLES E. HALL, of Skaneateles, in the county ofOnondaga and State of New York, have invented a new and ImprovedApparatus for ReiittingValve-Seats of Globe-Valves, of which thefollowing is a specification:

My invention consists of a kind of double coneshaped stock, withdifferential screwthreaded facets for fitting into different-sizedscrew-threaded holes in the shells ofthe valves to hold therefitting-tool, which stock has a screw-threaded central hole, in whichis a hollow threaded feed screw, which holds the shank of therefitting-tool in its central hole, and forces the tool down to its workby screwing in the aforesaid stock against a shoulder on the tool-shank.A jam-nut is provided on the feed screw, to hold it in any position towhich it may be adjusted by screwing against the stock, and prevent itfrom being turned by the shank of the tool, which is turned by a wrenchor crank applied to the end projecting up through the top or outer endof the feed-screw, all as hereinafter described.

Figure 1 is a vertical sectional elevation of my improved refittingapparatus and the shell of a globe-valve, showing the application of thetool to the valve-seat. Fig. 2 is a horizontal section of the apparatus,taken on the line :20 w.

Similar letters of reference indicate corresponding parts.

A represents the before-mentioned double conical-shaped stock, withdifferential screwthreaded facets B, by which it is adapted to fitshells O of different sizes, with holes D, varying in size, in whichholes the stock is to be screwed to hold the milling-tool E for dressingoff the valve-seat F, in the manner clearly indicated in Fig. 1. Themiddle facet B is used for turning the stock. This stock has a centrallongitudinal screw threaded hole application of a Wrench for turning it,andhaving a shoulder, M, against which the inner end of the feed-screwbears to .hold it to its work. The cutter is of the ordinary kind ofconical milling-tools used in dressing valveseats. 1

In using this apparatus, the screw H is screwed down against the tool,so as to press it on the valve-seat with considerable force, and madefast by the jam-nut. The wrench is then applied to the shank L, and thetool is turned as long as it continues to cut, working out a perfectlytrue face by being held without feeding forward, so that all the cutsultimately Vanish, and leave no marks or ridges.

Having thus described myinven tion, I claim as new and desire to secureby Letters Patent- The combination of the stock A, with differentialscrew-threaded facets, feed-screw H, jam-nut K, and the refitting-toolE, shank L, and collar M, substantially as specified.

CHARLES F. HALL.

Witnesses:

S. L. BENEDICT, F. B. BENEDICT.

